Reduced-Pressure Systems, Dressings, And Methods Facilitating Separation Of Electronic And Clinical Component Parts

ABSTRACT

Systems, dressings, and related methods, for providing reduced pressure to a tissue site on a patient are presented that involve using a self-contained reduced-pressure dressing. The dressing includes an absorbent pouch and an electronics pouch. The absorbent pouch has an absorbent for absorbing liquid from the tissue site, and the electronics pouch has a pump for applying reduced pressure to the tissue site through the absorbent pouch. The electronics pouch is removably coupled to the absorbent pouch such that the electronics pouch and absorbent pouch may be easily separated for disposal.

REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.14/386,444, filed Sep. 19, 2014, which is a National Stage Entry ofPCT/US2013/034472, filed Mar. 28, 2013, which claims benefit under 35USC 119(e), of the filing of U.S. Provisional Patent Application Ser.No. 61/616,901, filed Mar. 28, 2012 and is herein incorporated byreference in its entirety.

FIELD

The present disclosure relates generally to medical treatment systemsand, more particularly, but not by way of limitation, toreduced-pressure wound dressings, systems, and methods that facilitatethe separation of clinical waste and electronics waste for efficientdisposal.

BACKGROUND

Clinical studies and practice have shown that providing a reducedpressure in proximity to a tissue site augments and accelerates thegrowth of new tissue at the tissue site. The applications of thisphenomenon are numerous, but application of reduced pressure has beenparticularly successful in treating wounds. This treatment (frequentlyreferred to in the medical community as “negative pressure woundtherapy,” “reduced pressure therapy,” or “vacuum therapy”) provides anumber of benefits, which may include faster healing and increasedformulation of granulation tissue. Typically, when applied to openwounds, reduced pressure is applied to tissue through a porous pad orother manifold device of a reduced-pressure wound dressing. The porouspad distributes reduced pressure to the tissue and channels fluids thatare drawn from the tissue into the dressing. When the reduced pressuretherapy is completed or the reduced-pressure wound dressing is spent,the reduced-pressure wound dressing is removed from the tissue site anddiscarded.

SUMMARY

According to an illustrative embodiment, a reduced-pressure dressing forapplying reduced pressure treatment to a tissue site includes anabsorbent pouch and an electronics pouch. The absorbent pouch includes amanifold, an absorbent layer, and a first cover. The manifold layer isadapted to deliver reduced pressure to the tissue site, the absorbentlayer is in fluid communication with the manifold layer to absorb liquidfrom at least one of the manifold layer and the tissue site, and thefirst cover is positioned over the absorbent layer and the manifoldlayer to maintain the reduced pressure at the tissue site. Theelectronics pouch is removably coupled to the absorbent pouch, andincludes a pump and a second cover. The pump is adapted to provide fluidcommunication to the tissue site through at least one of the absorbentlayer and the manifold layer, and the second cover has a firstelectronics cover and a second electronics cover. The second electronicscover is coupled to the first electronics cover and the pump ispositioned between the first electronics cover and the secondelectronics cover.

Another illustrative embodiment includes a method for disposing of areduced-pressure dressing. The reduced-pressure dressing includes anelectronics pouch removably coupled to an absorbent pouch. The absorbentpouch includes a tissue manifold layer, an absorbent layer in fluidcommunication with the tissue manifold layer, and a first cover. Themethod comprises pulling the electronics pouch to separate electronicspouch from the absorbent pouch along a weakened coupling between theelectronics pouch and the absorbent pouch.

According to another illustrative embodiment, a reduced-pressuredressing for applying reduced pressure treatment to a tissue siteincludes an absorbent pouch and a pump pouch. The absorbent pouch has anabsorbent for absorbing liquid from the tissue site, and the pump pouchhas a pump for applying reduced pressure to the tissue site through theabsorbent pouch. The pump pouch is removably coupled to the absorbentpouch.

According to another illustrative embodiment, a reduced-pressuredressing for applying reduced pressure treatment to a tissue siteincludes a manifold layer and an absorbent layer. The manifold layer isadapted to be positioned at the tissue site and the absorbent layer isin fluid communication with the manifold layer. The reduced-pressuredressing includes a cover positioned over the absorbent layer to createa sealed space beneath the cover, and the cover has an aperture to allowfluid communication with the sealed space. The reduced-pressure dressingalso includes an envelope comprising an upper sheet coupled to a lowersheet, and a pump positioned between upper and lower sheets. Thereduced-pressure dressing includes a removable coupling between theenvelope and the cover.

Other features and advantages of the illustrative embodiments willbecome apparent with reference to the drawings and detailed descriptionthat follow.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side, cross-section view of an illustrative embodiment of asystem for treating a tissue site with reduced pressure, including areduced-pressure dressing coupled to the tissue site;

FIG. 2 is a side, cross-section view of the illustrativereduced-pressure dressing of FIG. 1, including a removable couplingbetween an electronics pouch and an absorbent pouch of thereduced-pressure dressing;

FIG. 2A is a detail view of a portion of the reduced-pressure dressingthat includes a perforation;

FIG. 3 is a top view of the reduced-pressure dressing;

FIG. 4 is a side, cross-section view of the reduced-pressure dressingthat shows the electronics pouch being separated from the absorbentpouch;

FIG. 5 is a side, cross-section view showing another illustrativereduced-pressure dressing having a removable coupling between theelectronics pouch and absorbent pouch of the reduced-pressure dressing;

FIG. 5A is a detail, cross-section view of the reduced-pressure dressingof FIG. 5;

FIG. 6A is a side, cross-section view of an illustrative embodiment of areduced-pressure dressing having an intermediate cover member and asealing member that comprises a first sealing member connector and asecond sealing member connector;

FIG. 6B is a detail, cross-section view of the reduced-pressure dressingof FIG. 6 in an exploded state;

FIG. 7 is a side, cross-section view of an illustrative reduced-pressuredressing having an intermediate cover member that comprises a firstcover connector and a second cover connector;

FIG. 8A is a top view of an illustrative embodiment of areduced-pressure dressing having an arcuate shape;

FIG. 8B is a perspective view showing the electronics pouch of thereduced-pressure dressing of FIG. 8A being separated from the absorbentpouch along a perforation; and

FIG. 9 is an exploded, perspective view of an illustrative embodiment ofa reduced pressure dressing having first envelope that is removablycoupled to a second envelope.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

In the following detailed description of the illustrative, non-limitingembodiments, reference is made to the accompanying drawings that form apart hereof. These illustrative embodiments are described in sufficientdetail to enable those skilled in the art to practice the invention. Itis understood that other embodiments may be utilized and that logicalstructural, mechanical, electrical, and chemical changes may be madewithout departing from the spirit or scope of the invention. To avoiddetail not necessary to enable those skilled in the art to practice theembodiments described herein, the description may omit certaininformation known to those skilled in the art. The following detaileddescription is not to be taken in a limiting sense, and the scope of theillustrative embodiments is defined only by the appended claims.

Wound dressings composed of traditional dressing materials typically donot contain electronic components. Yet recent and more advanced wounddressings include electronic components to deliver therapy to wounds andto monitor conditions at wound sites. This may pose a difficultly whenthe dressing has been used and the time comes to dispose of thedressing. Used wound dressings that include biological or clinical wasteare frequently required by law to be disposed by approved methods. Forexample, regulations may require the incineration of clinical waste tolimit the risk of spreading disease. Similarly, the disposal ofelectronic components is also regulated by law in many jurisdictions.Such regulations may require that used electronic components bedisassembled and recycled, or sent to a specific waste handling centerthat is equipped to dispose of electronic components with minimalenvironmental impact. The approved methods for disposing of clinicalwaste and electronic waste, however, are normally not compatible withone another. Thus, in the case of a used wound dressing that includeselectronic components, the electronic components may be separated fromthe clinical waste prior to disposal. After separation, the clinicalwaste portion and electronic waste portions of the spent wound dressingmay be sent to different facilities for disposal. Depending on theconfiguration of the wound dressing, however, separating the electronicsfrom the remainder of the wound dressing may be messy, impractical, andunsanitary.

The illustrative embodiments include a wound dressing that functions asa single unit to treat a wound but allows for the separation of theelectronic components from components that have absorbed clinical wasteprior to disposal. Such a wound dressing allows the appropriate disposalof the clinical waste and recycling of electronic components. Theillustrative embodiments also include wound dressing components that maybe recombined to enable a wound dressing to stay in place whileelectronic components, such as batteries, are replaced to extend thelife of the wound dressing.

The illustrative embodiments provide a reduced-pressure wound dressinghaving a reliable seal between dressing components that can be brokenapart without exposing a user or caregiver to unnecessary contact withfluids absorbed by the dressing. The reduced-pressure wound dressingallows for easy and appropriate disposal of the components depending onthe type of waste (e.g., as clinical waste or electronic waste). Inaddition, the illustrative embodiments provide an integrated wounddressing and reduced-pressure source (i.e., a pump) that may bemanufactured either as a single unit or as separate modules. Parts of amodular system may be manufactured in separate facilities and differentsterilization processes may be employed to different components of thesystem. For example, portions of the dressing that include electroniccomponents may be sterilized using Ethylene Oxide, Super Critical CarbonDioxide, or other sterilization methods that do not degrade theelectronics. Other portions of the dressing may be sterilized usingother methods, such as Gamma Irradiation or E-Beam sterilization,dependent on material compatibility. An illustrative reduced-pressuredressing alleviates the need for a remote reduced-pressure source ortherapy unit that is connected via a tube or conduit, as used by moretypical dressings that provide reduced pressure to a tissue site. Theillustrative reduced-pressure dressing is a self-contained dressing ortherapy unit that can be separated on disposal with minimal userintervention and effort.

In one embodiment, an absorbent, reduced-pressure dressing has anonboard reduced-pressure source, control system, and power source.Referring now to the drawings and initially to FIG. 1, an illustrativeembodiment of a system 100 for treating a tissue site 102, e.g., a wound104 or a cavity, with reduced pressure is presented. The tissue site 102may be, for example, the wound 104 extending through epidermis 156 andinto subcutaneous tissue 158, or any other tissue site. Reduced pressuregenerally refers to a pressure less than the ambient pressure at atissue site that is being subjected to treatment. In most cases, thisreduced pressure will be less than the atmospheric pressure at which thepatient is located. Alternatively, the reduced pressure may be less thana hydrostatic pressure at the tissue site 102. Unless otherwiseindicated, values of pressure stated herein are gauge pressures. Thereduced pressure delivered may be constant or varied (patterned orrandom) and may be delivered continuously or intermittently. Consistentwith the use herein, unless otherwise indicated, an increase in reducedpressure or vacuum pressure typically refers to a relative reduction inabsolute pressure.

The system 100 includes a reduced-pressure dressing 106 for disposingproximate to the tissue site 102. The reduced-pressure dressing 106includes absorbent materials and has the ability to deliver reducedpressure to the tissue site 102. The reduced-pressure dressing 106includes an absorbent pouch 114 fluidly sealed and mechanicallyconnected, or coupled, to an electronics pouch 116 by a removablecoupling 118 or a sealing member 154 that pneumatically connects thepouches. As used herein, the word “or” is not mutually exclusive. Theelectronics pouch 116 and absorbent pouch 114 are joined together suchthat there is a secure bond between the pouches. The secure bond may bea high-frequency weld around the periphery of the electronics pouch 116.FIGS. 2-9 show similar systems, and variation is shown between figuresin order to show some of the potential variations in the illustrativesystem 100.

The system 100 may be used with various different types of tissue sites102. The tissue site 102 may be the bodily tissue of any human, animal,or other organism, including bone tissue, adipose tissue, muscle tissue,dermal tissue, vascular tissue, connective tissue, cartilage, tendons,ligaments, body cavity or any other tissue. Treatment of the tissue site102 may include removal of fluids, e.g., exudate or ascites.

Referring again to FIG. 1, the electronics pouch 116 of thereduced-pressure dressing 106 is formed by coupling a first electronicscover 120 to a second electronics cover 122, wherein the secondelectronics cover 122 is on the patient-facing side of the electronicspouch 116. In one embodiment, one or more sub parts, e.g., sheets ofelastomeric film, form the first electronics cover 120 and the secondelectronics cover 122. The electronics pouch 116 may also be formed byother techniques such as casting or molding the electronics pouch 116from a polymer. The electronics pouch 116, or pump pouch, of FIG. 1includes a pump 108. Within the electronics pouch 116, the pump 108 ismounted to a substrate 132 that is formed from a printed circuit boardmaterial such as polyimide, phenolic or another suitable material. Theelectronics pouch may also include a processor, a power source, and acommunication system (not shown) that control the pump 108, power thepump 108, and transmit and receive data. In use, the pump 108 deliversreduced-pressure to the absorbent pouch 114 through an aperture 178 inthe substrate 132 that is coupled to the second electronics cover 122.The first electronics cover 120 of the electronics pouch 116 includes avent 176 to fluidly couple an exhaust from the pump 108 to an exteriorof the reduced-pressure dressing 106. An odor filter 177 may beinstalled within the vent 176 to prevent the reduced-pressure dressing106 from emitting odor from the wound 104.

The pump 108 may be a micro-pump device and may take numerous forms,such as a piezoelectric pump, peristaltic pump, or other miniaturizedpump. In one embodiment, the pump 108 is an acoustic resonance pump thatapplies the principle of acoustic resonance to generate pressureoscillations within a cavity and motivate fluid through the pump 108.The pump 108 may be the type of micro-pump shown in United States PatentPublication 2009/0240185 (application Ser. No. 12/398,904; filed 5 Mar.2009), entitled, “Dressing and Method for Applying Reduced Pressure Toand Collecting And Storing Fluid from a Tissue Site,” which isincorporated herein for all purposes.

The pump 108 is small and light enough to allow the reduced-pressuredressing 106 to be maintained on the tissue site 102 without causingdiscomfort to the patient. The size and weight of the micro-pump may besuch that the reduced-pressure dressing 106 does not pull or otherwiseadversely affect the tissue site 102. In one illustrative embodiment,the micro-pump may be a disc pump having a piezoelectric actuatorsimilar to that previously described. Reference is also made to thepumps shown in United States Patent Publication 2009/0087323 and UnitedStates Patent Publication 2009/0240185, which are hereby incorporated byreference for all purposes. It should be understood that alternativepump technologies may be utilized and that rotary, linear, or otherconfigurations of pumps may be utilized.

The pump 108 has sufficient flow, reduced pressure, and operation lifecharacteristics to enable continuous application of reduced pressuretreatment. The flow may range between about 5-1000 ml/min and thereduced pressure may range between about −50 and −200 mm Hg (−6.6 to−26.6 kPa). It should be understood that alternative ranges may beutilized depending on the configuration of the reduced-pressure dressing106, size of wound, or type of wound. In one illustrative embodiment,multiple pumps may be positioned in a single dressing to deliverincreased flow rates or vacuum levels as required.

In use, the pump 108 generates reduced pressure that is delivered to thetissue site 102 via the absorbent pouch 114. To deliver reduced-pressureto the tissue site 102, the pump 108 applies reduced-pressure throughthe aperture 178 in the substrate 132 or an aperture in the pump base ifno substrate 132 is present. In the embodiment of FIG. 1, a sealingmember 154 having a sealing member aperture 140 fluidly couples theelectronics pouch 116 to the absorbent pouch 114. The sealing member 154provides a fluid seal by coupling to, for example, the substrate 132 ofthe electronics pouch 116 and the absorbent pouch 114. In otherembodiments, the reduced-pressure dressing 106 omits the sealing member154 and the electronics pouch 116 and absorbent pouch 114 are fluidlycoupled by a direct coupling. When applying reduced-pressure to thetissue site 102, the absorbent pouch 114 may receive and retain fluidsfrom the tissue site 102.

In one embodiment, the sealing member 154 is a sealing ring thatprovides a pneumatic seal between the pump 108 and the absorbent pouch114. One side of the sealing ring may be bonded to the substrate 132 towhich the pump 108 is mounted and the other side of the sealing ring maybe bonded to the absorbent pouch 114.

The absorbent pouch 114 applies reduced pressure from the pump 108 tothe tissue site 102. The absorbent pouch 114 includes a manifold layer124 formed from a manifold material and is applied adjacent to thetissue site 102 to distribute reduced pressure. Generally, a manifold isa substance or structure that assists in applying reduced pressure to,delivering fluids to, or removing fluids from a tissue site 102. Themanifold layer 124 typically includes a plurality of flow channels orpathways that distribute fluids provided to and removed from the tissuesite 102 around the manifold layer 124. In one illustrative embodiment,the flow channels or pathways are interconnected to improve distributionof fluids provided to or removed from the tissue site 102. The manifoldlayer 124 may be a biocompatible material that is capable of beingplaced in contact with the tissue site 102 and distributing reducedpressure to the tissue site 102. Examples of materials used to form themanifold layer 124 may include without limitation the following:materials that have structural elements arranged to form flow channels,e.g., cellular foam, open-cell foam, porous tissue collections, liquids,gels, and foams that include, or cure to include, flow channels; foam;gauze; felted mat; or any other material suited to a particularbiological application.

In one embodiment, the manifold layer 124 is a porous foam and includesa plurality of interconnected cells or pores that act as flow channels.The porous foam may be a polyurethane, open-cell, reticulated foam suchas GranuFoam® material available from Kinetic Concepts, Incorporated ofSan Antonio, Tex. In some situations, the manifold layer 124 may also beused to distribute fluids such as medications, antibacterials, growthfactors, and various solutions to the tissue site 102. Other layers maybe included in or on manifold layer 124, such as absorptive materials,wicking materials, hydrophobic materials, and hydrophilic materials.

In one embodiment, the manifold layer 124 distributes reduced pressuregenerated by the pump 108 and may draw exudate from the wound 104. Toretain the exudate, the manifold layer 124 is coupled to an absorbentlayer 110 that functions to receive and retain fluids such as exudatefrom the tissue site 102. The absorbent layer 110 may be made from anymaterial capable of absorbing liquid. For example, the absorbent layer110 may be made from super absorbent fibers. The super absorbent fibersmay retain or bond to the liquid in conjunction with a physical orchemical change to the fibers. In one non-limiting example, the superabsorbent fiber may include the Super Absorbent Fiber (SAF) materialfrom Technical Absorbents, Ltd. of Grimsby, United Kingdom. Theabsorbent layer 110 may be a sheet or mat of fibrous material in whichthe fibers absorb liquid from the tissue site 102. The structure of theabsorbent layer 110 that contains the fibers may be either woven ornon-woven. The fibers in the absorbent layer 110 may gel upon contactwith the liquid, thereby trapping the liquid. Spaces or voids betweenthe fibers may allow reduced pressure that is applied to the absorbentlayer 110 to be transferred within and through the absorbent layer 110.

To prevent liquid (e.g., exudate) from escaping the absorbent pouch 114and entering the electronics pouch 116, a liquid-air separator 112,e.g., a hydrophobic filter, may be placed between absorbent layer 110and a first cover of the absorbent pouch 114. In such an embodiment, thefirst cover 126 of the absorbent pouch 114 is coupled about theperimeter of the sealing member 154 to form a fluid seal.

In an embodiment, an intermediate manifold may be applied between thereduced-pressure dressing 106 and a portion of the tissue site 102. Theintermediate manifold may be constructed from bioresorbable materialsthat may remain in a patient's body following use of thereduced-pressure dressing 106. Suitable bioresorbable materials mayinclude, without limitation, a polymeric blend of polylactic acid (PLA)and polyglycolic acid (PGA). The polymeric blend may also includewithout limitation polycarbonates, polyfumarates, and capralactones. Theintermediate manifold may further serve as a scaffold for newcell-growth, or a scaffold material may be used in conjunction with theintermediate manifold to promote cell-growth. A scaffold is a substanceor structure used to enhance or promote the growth of cells or formationof tissue, such as a three-dimensional porous structure that provides atemplate for cell growth. Illustrative examples of scaffold materialsinclude calcium phosphate, collagen, PLA/PGA, coral hydroxy apatites,carbonates, or processed allograft materials. In an embodiment, thereduced-pressure dressing 106 also includes an interface layer, orcomfort layer, for placing between the tissue site 102 and the manifoldlayer 124.

The absorbent pouch 114 maintains a fluid coupling with the tissue site102 to apply reduced-pressure. As such, the perimeter of the absorbentpouch 114 may be coupled to the tissue site 102 to form a sealed space.This coupling creates a fluid seal around the tissue site 102 that maybe achieved by coupling the first cover 126 of the absorbent pouch 114to the tissue site 102 using an attachment device. In such anembodiment, the first cover 126 is coupled to the manifold layer 124 ora comfort layer so that the absorbent layer 110 will maintain structuralintegrity when removed from the tissue site 102. In another embodiment,the first cover 126 is coupled to a second cover 128 in the mannerdescribed above with regard to the first electronics cover 120 andsecond electronics cover 122 of the electronics pouch 116. In anembodiment, the second cover 128 is coupled to the tissue site 102 tocreate the fluid seal when the reduced-pressure dressing 106 is appliedto the tissue site 102. Upon removal of the reduced-pressure dressing106 from the tissue site 102, the coupling between the first cover 126and second cover 128 prevents the layers of the absorbent pouch 114 fromseparating so that the absorbent pouch 114 may be discarded as a unit.

To maintain the fluid seal, the first cover 126 and second cover 128 ofthe absorbent pouch 114, and the first electronics cover 120 and secondelectronics cover 122 of the electronics pouch 116 may be formed from animpermeable or semi-permeable, elastomeric material. Elastomericmaterials have the properties of an elastomer or, more generally, apolymeric material that has rubber-like properties. More specifically,most elastomers have ultimate elongations greater than 100% and asignificant amount of resilience. The resilience of a material refers tothe material's ability to recover from an elastic deformation. Examplesof elastomers include, but are not limited to, natural rubbers,polyisoprene, styrene butadiene rubber, chloroprene rubber,polybutadiene, nitrile rubber, butyl rubber, ethylene propylene rubber,ethylene propylene diene monomer, chlorosulfonated polyethylene,polysulfide rubber, polyurethane (PU), EVA film, co-polyester, andsilicones. Additional, specific examples of dressing sealing membermaterials include a silicone drape, 3M Tegaderm® drape, polyurethane(PU) drape such as one available from Avery Dennison Corporation ofPasadena, Calif. The reduced-pressure dressing forms a sealed space overthe tissue site 102, which may or may not contain the pump 108. Theelastomeric material may be a tin, flexible elastomeric film.

An attachment device 162 may be used to couple the first cover 126 orsecond cover 128 to the patient's epidermis or another intermediatelayer, such as a gasket or additional sealing device. The attachmentdevice 162 may take numerous forms. For example, the attachment device162 may be a medically acceptable, pressure-sensitive adhesive thatextends about a periphery or all of the first cover 126 (or second cover128) or covers at least a portion of a patient-facing side of thereduced-pressure dressing 106 over the epidermis 156.

As noted above, the reduced-pressure dressing 106 includes the removablecoupling 118 between the electronics pouch 116 and the absorbent pouch114. The removable coupling 118 allows a caregiver to separate theelectronics pouch 116 from the absorbent pouch 114 by exerting a forceon a portion of the electronics pouch 116, such as tab 130. An exampleof such a removable coupling is described in more detail with regard toFIGS. 2-4.

Turning now to FIGS. 2-4, the reduced-pressure dressing 206 includes aremovable coupling 218 that facilitates the separation of theelectronics pouch 216 from the absorbent pouch 214 after use. Theremovable coupling 218 includes a first bond 236 and a second bond 238offset from the first bond 236. The first bond 236 and second bond 238may be any suitable type of joining technology, bond or coupling,including a high frequency weld, an ultrasonic weld, a heat weld, anadhesive bond, and a molded part line. In one embodiment, the first bond236 couples a second electronics cover 222 to a first cover 226 of anabsorbent pouch 214. The second bond 238 is offset from the first bond236 and further from the perimeter 278 of the reduced-pressure dressing206 than the first bond 236. The first bond 236 should be strong enoughso that unintended separation of the electronics pouch 216 from theabsorbent pouch 214 does not occur. The first bond 236 may be a weld orother joint that provides a pneumatic seal, but a pneumatic seal betweenthe pouches may instead be provided by another component or weld that iswithin the boundary of the first bond 236, such as a sealing member 254.A perforation 234 extends through the first electronics cover 220 andsecond electronics cover 222 between the first bond 236 and second bond238, i.e., inside of the first bond 236 but outside of the second bond238. The perforation 234 provides a separation line where the firstelectronics cover 220 and second electronics cover 222 can be torn toseparate the electronics pouch 216 from the absorbent pouch 214. Tofacilitate separation of the electronics pouch 216 from the absorbentpouch 214, the first electronics cover 220 may include a tab 230 bondedto the first electronics cover 220 using any of the bond types describedabove, or formed integrally to the first electronics cover 220.Alternatively, the first electronics cover 220 may include a hole thatallows a separation force to be exerted on the electronics pouch 216. Inone embodiment, pulling the tab 230 causes a tear to develop andpropagate along the weakened path of the perforation 234 until theelectronics pouch 216 separates from the absorbent pouch 214.

In one embodiment, the first bond 236 couples the second electronicscover 222 to both the first electronics cover 220 and first cover 226.In another embodiment, the first bond 236 couples the first electronicscover 220 to the second electronics cover 222. In such embodiments, thesecond electronics cover 222 couples to the first cover 226 at anysuitable location that is outside of the perforation 234 to preserve thecoupling of the electronics pouch 216 to the absorbent pouch 214 untilthe electronics pouch 216 is torn along the perforation 234.

The dimensions of the perforation 234 are dependent on the material usedto manufacture the electronics pouch 216 or absorbent pouch 214 as wellas the location of the perforation 234. The perforation 234 shouldweaken the material so that the strength of the perforated area issignificantly less than the tear strength of the pouch material. In anembodiment where the material is Exopack DEV 09-80A or Inspire 70980,the perforation 234 may have the dimensions of 0.1 mm land and between0.1 mm and 0.5 mm space.

FIG. 3 illustrates a possible arrangement of the first bond 236,perforation 234, and second bond 238 and FIG. 4 shows how theelectronics pouch 216 separates from the absorbent pouch 214 after beingtorn along the perforation 234. When separated, the portion of thereduced-pressure dressing 206 that retains the absorbent pouch 214 has afirst perforation line 234 a and the electronics pouch 216 has a secondperforation line 234 b indicating the points of separation. In theillustrative embodiment of FIGS. 2-4, the sealing member 254 is shown asbeing coupled to the patient-facing side of the electronics pouch 216and releasably coupled to the absorbent pouch 214. In anotherembodiment, however, the sealing member 254 is coupled to the absorbentpouch 214 and releasably coupled to the electronics pouch 216.

In an embodiment, the sealing member 254 is a sealing ring, and anadhesive is used to couple the sealing ring to the substrate 232 of thepump 208 or to the first cover 226 of the absorbent pouch 214. Theproperties of the adhesive applied to the surfaces of the sealing ringmay be altered so that when the pouches are separated, the sealing ringremains adhered to either the substrate 232 or the first cover 226. Ifthe sealing ring is attached by welding, the seal ring itself can have aweakened area to facilitate tearing to separate the sealing ring fromthe electronics pouch 216 or absorbent pouch 214 when the electronicspouch 216 is removed. The sealing ring may then be disposedappropriately. Adhesives that may be used to adhere the sealing ring tothe substrate 232 of the first cover 226 Acrylic Pressure SensitiveAdhesives (PSA) based such as 3M 927, or a UV liquid adhesive such asDymax 1201-M-SC.

The sealing member 254 may be a single flexible material that hasadhesive coating on each side to couple to the electronics pouch 216 andabsorbent pouch 214. The sealing member 254 also provides a fluid sealbetween the electronics pouch 216 and absorbent pouch 214. The flexiblematerial may be a closed cell foam, such as a foam manufactured fromneoprene or ethylene-vinyl acetate (EVA). Additionally, the flexiblematerial may provide a level of padding between the electronics pouch216 and absorbent pouch 214, thereby adding flexibility to thereduced-pressure dressing 206. In an embodiment, the sealing membermaterial may be a solid elastomeric material, such as a thermoplasticelastomer (TPE), or a rigid material. Where an adhesive is used to holdthe sealing member 254 in place, the adhesive properties can be alteredbetween the two sides of the sealing member 254 so that on separation,the sealing member 254 remains coupled to either the electronics pouch216 or the absorbent pouch 214.

In another embodiment, the electronics pouch 216 couples directly to theabsorbent pouch 214. In such an embodiment, a portion of the electronicspouch 216 or the absorbent pouch 214 may include a breakaway feature,such as a weakened area in the pouch material or a breakaway feature inthe substrate 232 to facilitate separation of the pouches.

Together, FIGS. 2-4 show that a caregiver may separate the electronicspouch 216 from the absorbent pouch 214 by grasping the tab 230 andexerting a force to tear the first electronics cover 220 and secondelectronics cover 222 around the perimeter of the electronics pouch 216.After generating the tear, the electronics pouch 216 may be grasped andpulled to apply pressure to the sealing member 254, which may be asealing ring. Once the sealing member 254 is separated from theelectronics pouch 216, the electronics pouch 216 is completely free fromthe absorbent pouch 214 and the pouches may be discarded separately.

FIG. 5 shows another illustrative embodiment of a reduced-pressuredressing 306 that is similar in many respects to the dressings of FIGS.1-4 but omits a second electronics cover. In the embodiment, an upperlayer of the absorbent pouch 314, such as the a liquid-air separator312, is coupled to the first cover 326 by a first bond 336. Inside ofthe first bond, the first cover 326 includes a perforation 334. Insideof the perforation 334, the first cover 326 is coupled to the firstelectronics cover 320 by a second bond 338. In this embodiment, thefirst cover 326 is also coupled to the substrate 332 that forms aportion of patient-facing side of the electronics pouch 316. Similar tothe embodiments of FIGS. 1-4, the reduced-pressure dressing 306 may betorn along the perforation 334 to separate the electronics pouch 316from the absorbent pouch 314. In this embodiment, the tab 330 may merelybe an extension of the first electronics cover 320.

FIGS. 6A and 6B show another illustrative embodiment of areduced-pressure dressing 406 having an electronics pouch 416 attachedto an absorbent pouch 414 by a removable coupling 418. In theembodiment, the first cover 426 of the absorbent pouch 414 is coupled toa proximate side of the sealing member 454. The opposing side of thesealing member 454 is coupled to the second electronics cover 422 or thesubstrate 432 of the electronics pouch 416. In addition, the first cover426 and first electronics cover 420 (or second electronics cover 422)are coupled to one another by the removable coupling 418, which is anintermediate cover member 450. The intermediate cover member 450 mayinclude a perforation or be formed of a material that is easier to tearthan the material that forms the pouches to facilitate separation of theelectronics pouch 416 from the absorbent pouch 414.

In an embodiment, the intermediate cover member 450 provides a fluidseal between the electronics pouch 416 and the absorbent pouch 414,thereby alleviating the need for a sealing member 454. The intermediatecover member 450 may add flexibility between the absorbent pouch 414 andelectronics pouch 416 in such an embodiment. The intermediate covermember 450 is bonded to the substrate 432 to which the pump 408 ismounted and bonded or welded to the first cover 426 of the absorbentpouch 414. The material that forms the intermediate cover member 450 isselected such that, when the electronics pouch 416 is separated from theabsorbent pouch 414, the intermediate cover member 450 will break beforethe integrity of either pouch is compromised. In another embodiment, theseparation occurs at either the bond between the intermediate covermember 450 and the absorbent pouch 414 or the bond between theintermediate cover member 450 and the electronics pouch 416.

In one embodiment, the sealing member 454 is formed from a first sealingconnector 442 coupled to the substrate 432 of the electronics pouch 416and a second sealing connector 444 coupled to the absorbent pouch 414.The first sealing connector 442 is releasably coupled to the secondsealing connector 444. As FIG. 6B shows, the releasable coupling betweenthe first sealing connector 442 and second sealing connector 444 resultsin the first sealing connector 442 remaining coupled to the electronicspouch 416 and the second sealing connector 444 remaining coupled to theabsorbent pouch 414 when the pouches are separated. In one embodimentthe sealing member 454 or second sealing connector 444 includesadditional elements, such as a liquid-air separator 446 and an odorfilter 448. Including the liquid-air separator 446 within the sealingmember 454 may alleviate the need for such an element in the absorbentpouch, enabling a smaller part to perform the function of preventingliquids (e.g., exudate) from entering the electronics pouch 416.Similarly, the sealing member 454 may include the odor filter 448, whichmay be a charcoal filter, thereby alleviating the need to install suchan element in another portion of the reduced-pressure dressing 406. Thesealing member 454 may be formed from a polymer, such as a polyvinylchloride (PVC) or acrylonitrile butadiene styrene (ABS) polymer. In anembodiment, the sealing member 454 may instead be formed frompolyurethane or another suitable material that is compatible with thepouch cover material and weldable using a high-frequency weldingprocess. In one embodiment, the sealing member 454 couples to the secondelectronics cover 422 or directly to the substrate 432 using anadhesive.

In one embodiment, a breakable connection piece is securely bonded toboth the electronics pouch 416 and absorbent pouch 414 to serve thefunction of both a sealing member 454 and intermediate cover member 450.In such an embodiment, the pouches may be separated by breaking thebreakable connection piece. Such a breakable connection piece may bemanufactured from a plastic molding having a weakened breakaway areathat causes the breakable connection piece to break in a predictable andcontrollable manner. The breakable connection piece may be made from aninjection molded thermoplastic polyurethane (TPU), such as Pellethane®2363-80AE having a durometer of 80 on the Shore A scale. The thicknessof the weakened area may be in the range of 0.05 mm to 0.08 mm, therebyenabling a controlled tear, or break, to be induced without riskingdamage or undesirable disassembly of the electronics pouch 416 orabsorbent pouch 414. In an embodiment, the breakable connection piececontains an odor filter and a liquid-air separator. The breakableconnection piece may also be manufactured from a porous polymer, e.g., asintered polymer, that has been treated to provide liquid and odorblocking functions. For example, the breakable connection piece mayinclude hydrophobic materials for liquid separation and activated carbonparticles for odor control. In the case of a sintered polymer material,the breakable connection piece would not include an aperture, but wouldbe a gas permeable structure having a sealed outer surface such that gaswould be pulled through the breakable connection piece to transmitreduced-pressure. In such an embodiment, the outer surface of thebreakable connection piece formed from the sintered polymer should becoated with a gas impermeable coating to provide a seal.

Where the intermediate cover member 450 is a breakable connection piecehaving a breakaway feature, the breakable connection piece may includean electrical connection. The electrical connection may electricallycouple one or more sensors in the absorbent layer 410 to the processorof the electronics pouch 416. In such an embodiment, thereduced-pressure dressing 406 may include sensors to measure the fluidcapacity of the dressing, the mechanical or pneumatic pressure at thetissue site, the pH of the wound, and other characteristics of thetissue site. The electrical coupling may also be used to provide powerto a therapeutic system mounted within the absorbent layer 410 thatrequires power or monitoring, such as a wound camera or electricalstimulation system. In such an embodiment, a RF device, such as a RFIDantenna, may be mounted in the reduced-pressure dressing 406 and thebreakable connection piece may provide additional space to mount relatedelectrical components. In addition, the breakable connection piece mayprovide multiple channels or lumens from the electronics pouch 416 tothe absorbent pouch 414, which may enable the monitoring of pressure inspecific areas of the reduced-pressure dressing. In such an embodiment,a TRAC system may be used to determine absorbent saturation or othercharacteristics of a tissue site where substances are being delivered toa wound. In such an embodiment, the reduced-pressure dressing may beconfigured to deliver anti-microbial agents, analgesics, and cleansingsolutions.

In another embodiment, the intermediate cover member 450 is an adhesivelayer that provides a fluid seal between the electronics pouch 416 andabsorbent pouch 414. The adhesive layer may be configured to allow theelectronics pouch 416 to be separated from the absorbent pouch 414 bypeeling the pouches apart.

Alternatively, the intermediate cover member 450 may be a film joined tothe electronics pouch 416 and absorbent pouch 414 by a suitable method,such as bonding or welding. The film may be manufactured so that thefilm is weaker than the adjacent materials, thereby allowing the film tobreak instead of the adjacent electronics pouch 416 and absorbent pouch414 as the pouches are pulled apart. Alternatively, a separationmechanism such as a string or strip of material is included beneath thefilm, such that pulling the string outward will cause the string orstrip to unwind and tear the film to facilitate separation of thepouches.

FIG. 7 shows another illustrative embodiment of a reduced-pressuredressing 506 that includes an electronics pouch 516 and an absorbentpouch 514. In the embodiment, reduced-pressure is transmitted from apump 508 of the electronics pouch 516 to the absorbent pouch 514 viasealing member 554. The electronics pouch 516 is coupled to theabsorbent pouch 514 by an intermediate cover member 550 that ismanufactured from multiple parts, such as a first cover connector 562and a second cover connector 564. The first cover connector 562 andsecond cover connector 564 are formed from different polymers so thatadhesion between the first cover connector 562 and second coverconnector 564 is strong enough to provide a fluid seal but weak enoughto be easily broken. For example, if the first cover connector 562 isfabricated from polyurethane, then the second cover connector may beformed from polypropylene or high-impact polystyrene. In addition, thesecond cover connector 564 may be formed from polyurethane or anothersuitable material that is compatible with the pouch cover material andweldable using a HF welding process. In an embodiment, a fluid sealbetween the first cover connector 562 and second cover connector 564 isobtained by an interference fit between the connectors. As such, thefirst cover connector 562 and second cover connector 546 may be matingparts having a snap fit or twist-lock feature with sealing surfaces tomaintain a fluid seal. The first cover connector 562 is coupled to thefirst cover 526 of the absorbent pouch 514 by an adhesive or weld, or byforming the first cover connector integrally to the first cover 526. Thesecond cover connector 564 couples to the electronics pouch 516 in asimilar manner.

In an embodiment having the first cover connector 562 and second coverconnector 564, one of the parts, e.g., the first cover connector 562 maybe manufactured by injection molding. The second cover connector 564 isthen combined with the first cover connector 562 using an overmoldingprocess. The overmolding process allows different materials to be usedthat are optimized for the joining process used at each interface. Forexample, the first cover connector 562 may be suitable for welding to apolymer surface of the absorbent pouch 514 while the second coverconnector 564 is better suited for adhesive bonding to a surface of theelectronics pouch 516 (e.g., to a polyimide or phenolic PCB substrate).

To form the second cover connector 564, the first cover connector 562 isinstalled in a mold, which is used to form the second cover connector564 by overmolding the second cover connector 564 to the first coverconnector 562. The overmolding process results in a part line 566 at thejunction of the first cover connector 562 and second cover connector564. The part line 566 may be formed such that when a separation forceis applied to the pouches, the electronics pouch 516 separates from theabsorbent pouch 514 along the part line 566. The part line 566 may be aflat surface or may include a mechanical interlock feature that enhancessealing. Where the fluid seal is enhanced by an interlock feature, thepolymeric bond between the first cover connector 562 and second coverconnector 564 is less important for the purposes of creating a fluidseal, and a weaker bond may be acceptable. As such, the first coverconnector 562 and the second cover connector 564 may be formed fromdissimilar materials that will not form a strong bond to one another.Also, a coating may be applied to the first cover connector 562 alongthe part line 566 to prevent the second cover connector 564 frompermanently bonding to the first cover connector 562. In this way, thefirst cover connector 562 may be removably coupled to the second coverconnector 564 to maintain a fluid seal until the electronics pouch 516is separated from the absorbent pouch 514.

A fluid seal between the first cover connector 562 and second coverconnector 564 may be more easily obtained by using an overmoldingprocess than another manufacturing process because manufacturingtolerances and dimensional variations at the interface are negated bythe overmolding process. The overmolding process also facilitates thejoining of dissimilar materials. For example, in an embodiment in whichthere is a difference in hardness between the first cover connector 562and the second cover connector 564, the connector formed from the softerpolymer is formed using the overmolding process, while the opposingconnector is formed using the injection molding process.

The use of dissimilar materials may also facilitate separation. Wherethe first cover connector 562 and second cover connector 564 includemechanical interlocking features, the softer connector may be moreeasily deformed to separate from the harder connector. In anotherembodiment both the first cover connector 562 and second cover connector564 are injection molded and assembled together to provide a sealedcoupling. In embodiments in which a more rigid part is manufactured froma material other than a thermoplastic (e.g., thermoset polymer), othermanufacturing techniques may be employed.

In an embodiment, the absorbent pouch 514 remains in place at a tissuesite while the electronics pouch 516 is removed to, for example, renewthe power source of the pump 508. The power source of the pump 508 maybe replaced within the electronics pouch 516 and the electronics pouch516 may be reapplied or replaced with a new electronics pouch 516 toextend the life of the reduced-pressure dressing 506.

FIGS. 8A and 8B show an embodiment of a reduced-pressured dressing 606having an arcuate shape. Aside from the arcuate shape, thereduced-pressure dressing 606 is generally analogous to the dressing ofFIG. 1. For example, the reduced-pressure dressing 606 includes anabsorbent pouch 614 having a first cover 626. The absorbent pouch 614receives reduced-pressure from a pump that is housed within anelectronics pouch 616. The electronics pouch 616 is removably coupled toabsorbent pouch at a first bond 636 and a second bond 638. Adjacent thesecond bond 638, the reduced-pressure dressing 606 includes aperforation 634 that facilitates the separation of the absorbent pouch614 from the electronics pouch 616. The first cover 620 of theelectronics pouch 616 includes a tab 630 that can be pulled to initiatea tear along the perforation 634 to separate the pouches.

FIG. 9 shows an exploded view of a reduced-pressure dressing 706 thatcontains additional layers but is similar in many respects to thedressings discussed above. The reduced-pressure dressing 706 is shown ina rectangular form but may be formed to have any suitable shape forapplication to a tissue site. For example, the reduced-pressure dressingmay be shaped to resemble the reduced-pressure dressing 606 of FIGS. 8Aand 8B.

The reduced-pressure dressing 706 includes an optional intermediatemanifold 768 that may be placed adjacent the tissue site, as discussedabove. The reduced-pressure dressing 706 includes a first cover 726 anda second cover 728. The second cover 728 has a first side 780 and asecond, patient-facing side 781. The second, patient-facing side 781 maybe coated with a releasable adhesive to facilitate application to atissue site. The second cover 728 also includes a treatment aperture 782for placing over a portion of the tissue site (e.g., a wound) thatreceives reduced pressure. The reduced-pressure dressing 706 alsoincludes a manifold layer 724, which is an internal distributionmanifold having a first side 783 and a second, patient-facing side 784.In use, the manifold layer 724 distributes reduced-pressure to thetissue site. The second, patient-facing side 784 of the manifold layer724 is coupled to the first side 780 of the second cover 728. Anabsorbent layer 710, which functions to receive and retain fluids from atissue site, is coupled to the manifold layer 724.

A diverter layer 770 is coupled to the absorbent layer 710. The diverterlayer 770 is disposed adjacent to the absorbent layer 710 and themanifold layer 724. The diverter layer 770 is formed from a liquidimpermeable material but contains a plurality of apertures 785. Theplurality of apertures 785 allow reduced pressure to be transmittedthrough the diverter layer 770 at desired locations. The diverter layer770 helps control the pattern of reduced pressure as applied to theabsorbent layer 710. The reduced pressure is distributed to the diverterlayer 770 by a second manifold layer 772 that is coupled to the diverterlayer 770. The apertures 785 may be arranged in a pattern for applyingthe reduced pressure to portions of the absorbent layer 710 to enhancethe capability of the absorbent layer 710 to continue transferringreduced pressure to the tissue site as the absorbent layer 710 absorbsmore fluid from the tissue site. The diverter layer 770 acts inconjunction with the second manifold layer 772 to ensure that theabsorption capabilities and absorption efficiency of the absorbent layer710 are increased relative to an absorbent layer 710 that is not used inconjunction with a diverter layer 770. By providing better distributionof liquid throughout the absorbent layer 710, the diverter layer 770also increases the effective capacity and treatment time of thereduced-pressure dressing 706.

The diverter layer 770 may be made from any material that enhances thereduced pressure transmission and storage capabilities of an adjacentabsorbent layer. For example, the diverter layer 770 may be made from amaterial that is substantially impermeable to liquid and gas and thatdiverts the reduced pressure to pass through apertures 785.Alternatively or in addition, the material from which the diverter layer770 is made may have a predetermined moisture vapor transfer rate thatis consistent with gas permeability. In either example, the diverterlayer 770 may still include a pattern of apertures for transmitting agreater volume of liquid or gas than that permitted by a gas-permeablematerial not having apertures. It should be noted, however, thatpermeability of the diverter layer 770 to gas but not liquid may resultin increased transmission of reduced pressure through the dressing whilestill directing liquid flow around or near the perimeter of the diverterlayer 770.

In this embodiment, the reduced-pressure dressing 706 includes aliquid-air separator 712 coupled to the second manifold layer 772 andthe first cover 726, which is coupled about the perimeter to the secondcover 728. The first cover 726 includes an aperture 788 to receivereduced pressure. Together, the first cover 726 and second cover 728form a first envelope 786 enclosing the manifold layer 724, absorbentlayer 710, diverter layer 770, second manifold layer 772, and liquid-airseparator 712.

To generate reduced pressure, the reduced-pressure dressing 706 includesa pump 708. The pump is mounted to a substrate 732 and coupled to aprocessor 760 and a power source 774. Additional electronic componentsmay be coupled to the pump 708, processor 760, or power source 774 asdesired. The substrate 732 is enclosed between a first electronics cover720, which is coupled to a second electronics cover 722 to form a secondenvelope 787. The first electronics cover 722 also includes a vent 776to fluidly couple an exhaust of the pump 708 to the external environmentand an odor filter may be installed between the exhaust of the pump 708and the vent 776 to prevent odor from a wound from escaping thereduced-pressure dressing 706. The substrate 732 and second electronicscover 722 also include apertures to facilitate the transmission ofreduced pressure to the first envelope 786.

The second envelope 787 is removably coupled to the first envelope 786using a removable coupling that provides a fluid seal. For example, aportion of the second electronics cover 722 may be coupled to a portionof the second cover 728. Optionally, a sealing member 754 provides asealed fluid path between the second envelope 787 and the first envelope786. The sealing member 754 includes an aperture for transmittingreduced-pressure generated by the pump 708 to the layers of the firstenvelope 786 for application to the tissue site.

Although the present invention and its advantages have been disclosed inthe context of certain illustrative, non-limiting embodiments, it shouldbe understood that various changes, substitutions, permutations, andalterations can be made without departing from the scope of theinvention as defined by the appended claims. It will be appreciated thatany feature that is described in connection to any one embodiment mayalso be applicable to any other embodiment.

It will be understood that the benefits and advantages described abovemay relate to one embodiment or may relate to several embodiments. Itwill further be understood that reference to “an” item refers to one ormore of those items.

The steps of the methods described herein may be carried out in anysuitable order, or simultaneously where appropriate.

Where appropriate, aspects of any of the embodiments described above maybe combined with aspects of any of the other embodiments described toform further examples having comparable or different properties andaddressing the same or different problems.

It will be understood that the above description of preferredembodiments is given by way of example only and that variousmodifications may be made by those skilled in the art. The abovespecification, examples and data provide a complete description of thestructure and use of exemplary embodiments of the invention. Althoughvarious embodiments of the invention have been described above with acertain degree of particularity, or with reference to one or moreindividual embodiments, those skilled in the art could make numerousalterations to the disclosed embodiments without departing from thescope of the claims.

1.-26. (canceled)
 27. A method for disposing of a reduced-pressuredressing comprising a second pouch removably coupled to a first pouch,the first pouch comprising a tissue manifold layer, an absorbent layerin fluid communication with the tissue manifold layer, and a firstcover, the method comprising: pulling the second pouch to separatesecond pouch from the first pouch along a weakened coupling between thesecond pouch and the first pouch.
 28. The method of claim 27, whereinthe weakened coupling comprises a perforation and wherein the secondpouch comprises a pump, a second pouch cover, and a substrate.
 29. Themethod of claim 27, wherein the weakened coupling is an intermediatecover member that tears more easily than the first cover and the secondpouch cover, and wherein the second pouch comprises a pump, a firstelectronics cover, and a substrate.
 30. The method of claim 27, whereinthe weakened coupling comprises an interface between a first coverconnector and a second cover connector, and wherein the second pouchcomprises a pump, a first electronics cover, and a substrate.
 31. Themethod of claim 27, wherein the weakened coupling comprises an adhesivelayer coupled to the first pouch and the second pouch, and wherein thesecond pouch comprises a pump, a first electronics cover, and asubstrate.
 32. The method of claim 31, wherein the adhesive layer iscoupled to the first cover and the substrate.
 33. The method of claim27, wherein the reduced-pressure dressing further comprises a sealingmember coupled to the second pouch and the first pouch, and the secondpouch comprises a pump, a first electronics cover, and a substrate, themethod further comprising: separating the sealing member from one of thefirst pouch and the second pouch.
 34. A reduced-pressure dressing forapplying reduced pressure treatment to a tissue site, thereduced-pressure dressing comprising: an absorbent pouch having anabsorbent for absorbing liquid from the tissue site; a pump pouch havinga pump for applying reduced pressure to the tissue site through theabsorbent pouch, the pump pouch removably coupled to the absorbentpouch.
 35. The reduced-pressure dressing of claim 34, wherein: the pumppouch comprises a perforation and a tab, the perforation operable totear in response to the application of a separating force to the tab.36. The reduced-pressure dressing of claim 34, wherein: the pump pouchcomprises a circuit board; the pump is mounted to the circuit board; thereduced-pressure dressing comprises a sealing member coupled to thecircuit board and the absorbent pouch; and the sealing member provides afluid seal between the pump and the absorbent pouch.
 37. Thereduced-pressure dressing of claim 36, wherein the sealing membercomprises a sealing ring.
 38. The reduced-pressure dressing of claim 36,wherein the sealing member comprises a first sealing connector and asecond sealing connector.
 39. The reduced-pressure dressing of claim 34,wherein the pump pouch is coupled to the absorbent pouch by a firstcover connector and a second cover connector.
 40. The reduced-pressuredressing of claim 34, wherein: the pump pouch is coupled to theabsorbent pouch by an intermediate cover member; the intermediate covermember is more susceptible to tearing than the pump pouch and theabsorbent pouch; and the pump pouch and absorbent pouch are separable bytearing the intermediate cover member.
 41. The reduced-pressure dressingof claim 34, wherein the pump is a piezoelectric-driven micropump.
 42. Areduced-pressure dressing for applying reduced pressure treatment to atissue site, the reduced-pressure dressing comprising: a manifold layeradapted to be positioned at the tissue site; an absorbent layer in fluidcommunication with the manifold layer; a cover positioned over theabsorbent layer to create a sealed space beneath the cover, the coverhaving an aperture to allow fluid communication with the sealed space;an envelope comprising an upper sheet and a lower sheet, the lower sheetcoupled to the upper sheet, and a pump positioned between upper andlower sheets; and a removable coupling between the envelope and thecover.
 43. The reduced-pressure dressing of claim 42, wherein: theenvelope comprises a perforation and a tab, the perforation operable totear in response to the application of a separating force to the tab.44. The reduced-pressure dressing of claim 42, wherein: the envelopecomprises a circuit board; the pump is mounted to the circuit board; andthe reduced-pressure dressing comprises a sealing member coupled to thecircuit board and the cover, wherein the sealing member provides a fluidseal between the pump and the cover.
 45. The reduced-pressure dressingof claim 44, wherein the sealing member comprises a sealing ring. 46.The reduced-pressure dressing of claim 44, wherein the sealing membercomprises a first sealing connector and a second sealing connector. 47.The reduced-pressure dressing of claim 42, wherein the envelope iscoupled to the cover by a first cover connector and a second coverconnector.
 48. The reduced-pressure dressing of claim 42, wherein: theenvelope is coupled to cover by an intermediate cover member; theintermediate cover member is more susceptible to tearing than the cover,the upper sheet, and the lower sheet; and the envelope and absorbentpouch are separable by tearing the intermediate cover member.
 49. Thereduced-pressure dressing of claim 42, wherein the pump is apiezoelectric-driven micropump.